U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000
Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
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This report is an archived publication and may contain dated technical, contact, and link information |
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Publication Number: FHWA-HRT-06-139
Date: October 2006 |
PDF files can be viewed with the Acrobat® Reader®
Research, Development, and Technology
Turner-Fairbank Highway Research Center
6300 Georgetown Pike
McLean, VA 22101-2296
The objective of the third edition of the Traffic Detector Handbook is to provide a comprehensive reference document to aid the practicing traffic engineer, planner, or technician in selecting, designing, installing, and maintaining traffic sensors for signalized intersections and freeways. Judicious application of the concepts and procedures set forth in the Handbook should result in improved installations and operations of traffic sensors and a long-term savings of public funds.
Sensor types include both in-roadway and over-roadway sensors. Topics covered include sensor technology, sensor applications, in-roadway sensor design, sensor installation techniques and sensor maintenance. The sensor technology chapter discusses the operation and uses of inductive loop detectors, magnetic sensors and detectors, video image processors, microwave radar sensors, laser radars, passive infrared and passive acoustic array sensors, and ultrasonic sensors, plus combinations of sensor technologies. Sensor application topics include safety, operation, multimodal issues, and physical and economic factors that affect installation and performance. The appendixes include a variety of research, background papers, and implementation guidance. The information contained in this Handbook is based on the latest research on available treatments and best practices in use by jurisdictions across the United States and elsewhere. References are provided for the student, practitioner, researcher, or decisionmaker who wishes to learn more about a particular subject.
The third edition is published in two volumes, of which this is the second, Volume II (FHWA-HRT-06-139), containing Chapters 5 and 6 and all Appendixes. Volume I (FHWA-HRT-06-108) contains Chapters 1 through 4.
Antoinette Wilbur, Director
Office of Operations
Research and Development
NOTICE
This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. This report does not constitute a standard, specification, or regulation.
The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers' names appear in this report only because they are considered essential to the objective of the document.
QUALITY ASSURANCE STATEMENT
The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement.
Technical Report Documentation Page
1. Report No. FHWA-HRT-06-139 |
2. Government Accession No. | 3. Recipient’s Catalog No. | |
4. Title and Subtitle Traffic Detector Handbook: Third Edition–Volume II | 5. Report Date October 2006 | ||
6. Performing Organization Code | |||
7.Author(s) Principal Author: Lawrence A. Klein Coauthors: Milton K. Mills, David R.P. Gibson |
8. Performing Organization Report No. | ||
9. Performing Organization Name and Address Lawrence A. Klein 3 Via San Remo Rancho Palos Verdes, CA 90275 | 10. Work Unit No. (TRAIS) | ||
11. Contract or Grant No. Contract No. DTFH61-03-P00317 | |||
12. Sponsoring Agency Name and Address 12. Sponsoring Agency Name and Address Federal Highway Administration Turner-Fairbank Highway Research Center 6300 Georgetown Pike, HRDO-04, Room No. T204 McLean, VA 22101-2296 | 13. Type of Report and Period Covered Implementation Package | ||
14. Sponsoring Agency’s Code | |||
15. Supplementary Notes David R.P. Gibson (David.Gibson@fhwa.dot.gov) at the Turner-Fairbank Highway Research Center (http://www.fhwa.dot.gov/research/tfhrc/) was the Technical Representative for the Federal Highway Administration (FHWA). Milton K. Mills, Advanced Research Team FHWA, contributed many technical papers. Traffic sensor researchers and practitioners contributed significantly to document organization, content, and exhibits. The peer review panel, consisting of Darcy Bullock of Purdue University, Dan Middleton of Texas Transportation Institute, and Tom Urbanik of the University of Tennessee, provided peer review and advice based on their use and testing of sensors. Tom Potter of Reno A&E gave technical advice on the electrical functioning of loop detectors. Sensor vendors provided technical information and exhibits on their technologies. In addition, many FHWA staff members participated as sensor group members and/or provided comments throughout the project, including Pamela Crenshaw, Ralph Gillman, Peter Huang, David Jones, and Raj Ghaman. |
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16. Abstract The objective of this Handbook is to provide a comprehensive resource for selecting, designing, installing, and maintaining traffic sensors for signalized intersections and freeways. It is intended for use by traffic engineers and technicians having responsibility for traffic sensors, whether in-roadway or over-roadway sensors. These two families of sensors have different characteristics and thus corresponding advantages and disadvantages that are discussed throughout the Handbook. Topics covered include sensor technology, applications, in-roadway sensor design, installation techniques, and maintenance. The sensor technology chapter discusses the operation and uses of inductive loop detectors, magnetic sensors and detectors, video image processors, microwave radar sensors, laser radars, passive infrared and passive acoustic array sensors, and ultrasonic sensors, plus combinations of sensor technologies. The sensor application topics addresses safety, operational performance, multimodal issues, and physical and economic factors that the practitioner should consider. Appendixes include research, background papers, and implementation guidance. The information contained in this Handbook is based on the latest research available on treatments and best practices in use by the surveyed jurisdictions. References are provided for the student, practitioner, researcher, or decisionmaker who wishes to learn more about a particular subject. The third edition is published in two volumes, of which this is the second, Volume II (FHWA-HRT-06-139), containing Chapters 5 and 6 and all Appendixes. Volume I (FHWA-HRT-06-108) contains Chapters 1 through 4. | |||
17. Key Words Traffic detectors, sensors, detector installation, detector maintenance, signalized intersections, intersection safety, intersection treatments, infrared sensor, inductive loop, magnetometer, video image processor, microwave radar sensor, laser radar sensor, acoustic sensor, ultrasonic sensor, magnetic sensor. | 18. Distribution Statement No restrictions. This document is available to the public through the National Information Technical Service, Springfield, VA, 22161 and Research and Technology Product Distribution Center, 9701 Philadelphia Court, Unit Q, Lanham, MD 20706; telephone: 301–577–0818; fax: 301–577–1421. | ||
19. Security Classif. (of this report) Unclassified | 20. Security Classif. (of this page) Unclassified | 21. No. of Pages 394 | 22. Price |
Form DOT F 1700.7 (8-72) | Reproduction of completed page authorized. |
SI* (Modern Metric) Conversion Factors
Chapter 3. Sensor Applications
Chapter 4. In-Roadway Sensor Design
CHAPTER 5. SENSOR-INSTALLATION TECHNIQUES
TYPICAL PREINSTALLATION ACTIVITIES
SCALE DRAWING OF SENSOR INSTALLATION SITE
FIELD VISITS
INSTALLATION CREW ESTIMATES
EQUIPMENT REQUIREMENTS
MATERIAL REQUIREMENTS
INDUCTIVE-LOOP DETECTOR INSTALLATION
INSTALLATION TECHNIQUES
INDUCTIVE-LOOP DETECTOR FAILURES
Causes of Inductive-Loop Detector Failures
Failure Frequency
Failure Mechanisms
LOOP LAYOUT AND SAWCUTS
Corner Treatment
Saw-Cutting Operations
Overview of Saw-Cutting Equipment
Diamond-Blade Design
Saw-Blade Troubleshooting
Saw Horsepower
Wet Versus Dry Cutting
Sawcut Depth
Finishing the Sawcut
INSTALLING LOOP WIRE
Wire Type
Ducted Wire
Prewound Loops
Preformed Loops
Metal-Sheathed Loop Cable
Wire Insertion
CROSSING PAVEMENT JOINTS
TWISTING THE LOOP WIRE LEAD-IN
CROSSING CURBS
INSTALLATION OF PULL BOX AND CONDUIT
TESTING THE LOOP
SEALING THE SAWCUT
Types of Sealants
Sealant Application Techniques
SPLICING THE WIRE
Connecting the Wires
Sealing the Splice from the Operating Environment
LEAD-IN CABLE INSTALLATION
FINAL TESTS AND RECORD KEEPING
GENERAL INSTALLATION GUIDELINES
INDUCTIVE-LOOP DETECTOR INSTALLATION ALTERNATIVES
SLAB LOOPS
ROUND LOOPS
Round-Loop Installation in Roadways
Round-Loop Installation on Sidewalks
INSTALLATION OF TWO-AXIS FLUXGATE MAGNETOMETERS
INSTALLATION OF SENSING PROBE
SPLICING THE CABLES
TESTING THE SYSTEM
SEALING THE HOLES AND CUTS
INSTALLATION OF MAGNETIC DETECTORS
INSTALLATION PROCEDURE
TRENCHING
CONNECTING THE SYSTEM
TESTING THE SYSTEM
OVER-ROADWAY SENSOR INSTALLATION
INITIAL SENSOR EVALUATIONS
VIDEO IMAGE PROCESSORS
SITE SURVEYS
LENS SELECTION
CALIBRATION ISSUES
SERIAL DATA INTERPRETATION SOFTWARE
AUTOSCOPE 2004 VIDEO IMAGE PROCESSOR DETECTION ZONES
TRAFICON VIP2 VIDEO IMAGE PROCESSOR DETECTION ZONES
MICROWAVE RADAR SENSORS
WHELEN TDN-30 CW DOPPLER SENSOR
MICROWAVE SENSORS TC-20 CW DOPPLER SENSOR
EIS RTMS FMCW RADAR
ACCUWAVE 150LX FMCW RADAR
LASER RADAR SENSORS
PASSIVE INFRARED SENSORS
ULTRASONIC SENSORS
PASSIVE ACOUSTIC SENSORS
IRD SMARTSONIC SINGLE-LANE ACOUSTIC SENSOR
SMARTEK SAS-1 MULTIPLE-LANE ACOUSTIC SENSOR
SENSOR COMBINATIONS
REFERENCES
CHAPTER 6. SENSOR MAINTENANCE
NATURE OF THE PROBLEM
FAILURE MODES IN INDUCTIVE-LOOP DETECTOR SYSTEMS
FAILURE MECHANISMS
Omitted Phase
Stuck Signal
Phase Extending to Maximum
Intermittent Problems
Crosstalk
Splashover
CAUSES OF LOOP SYSTEM FAILURE
FACTORS AFFECTING REQUIRED MAINTENANCE
TROUBLESHOOTING PROCEDURES FOR INDUCTIVE-LOOP DETECTORS
SAWCUT MAINTENANCE
REARRANGEMENT OF LOOP CONNECTIONS
ELIMINATING CROSSTALK
SUBSTITUTION OF ELECTRONICS UNITS
OPERATIONAL CHECK OF MALFUNCTIONING INDUCTIVE-LOOP DETECTOR
Adjacent Lane Detection
Intermittent Operation
System Sensitivity
ELECTRICAL TESTING OF AN INDUCTIVE-LOOP DETECTOR SYSTEM
TEST PROCEDURES
Sequential Test Procedure
Step 1. Conduct Visual Inspection
Step 2. Check Operation of Inductive-Loop Electronics Unit
Step 3. Measure Parameters Needed To Determine Quality Factor Q
Step 4. Determine Q
Step 5. Measure Sensitivity of Inductive-Loop System
Method 1
Method 2
Step 6. Analysis
MAGNETOMETER SYSTEM MAINTENANCE
CAUSES OF MAGNETOMETER FAILURES.6-17
Probe Burial Depth
Probe Movement
Probe Cable
Sawcut Maintenance
TROUBLESHOOTING PROCEDURES
MAGNETIC DETECTOR MAINTENANCE
OVER-ROADWAY SENSOR MAINTENANCE
VIDEO IMAGE PROCESSORS
MICROWAVE RADAR SENSORS
MAINTENANCE COST COMPARISONS AMONG SENSOR TECHNOLOGIES
REFERENCES
APPENDIX A. INDUCTIVE-LOOP SYSTEM EQUIVALENT CIRCUIT MODEL
ABSTRACT
INTRODUCTION
LOOP CAPACITANCE THEORY
INTERNAL-LOOP CAPACITANCE
EXTERNAL-LOOP CAPACITANCE
LOOP RESISTANCE THEORY
LOOP RESISTANCE
INTERNAL INDUCTANCE AND RESISTANCE PER UNIT LENGTH FOR A CYLINDRICAL CONDUCTOR
LOOP-INDUCTANCE THEORY
SELF-INDUCTANCE OF SINGLE-TURN CIRCULAR LOOP
SELF-INDUCTANCE OF MULTITURN CIRCULAR LOOP
EXTERNAL INDUCTANCE OF SINGLE-TURN RECTANGULAR LOOP
SELF-INDUCTANCE OF SINGLE-TURN RECTANGULAR LOOP
SELF-INDUCTANCE OF MULTITURN RECTANGULAR LOOP
MUTUAL INDUCTANCE OF PARALLEL FILAMENTARY CIRCUITS
MUTUAL INDUCTANCE OF TWO COAXIAL AND PARALLEL RECTANGULAR LOOPS
SELF-INDUCTANCE OF MULTITURN QUADRUPOLE LOOP
GENERAL FORMULA FOR MUTUAL INDUCTANCE OF PARALLEL FILAMENTS
INDUCTIVE-LOOP CIRCUIT MODEL
LOOP TRANSMISSION LINE THEORY
LOOP TRANSMISSION LINE MODEL
FREQUENCY SHIFT ELECTRONICS UNIT SENSITIVITY
LOOP TRANSFORMER THEORY
INDUCTIVE-LOOP TRANSFORMER MODEL
LOOP-DETECTOR ANALYSIS SYSTEM PROGRAM
COMPARISON OF CALCULATED AND MEASURED LOOP SELF-INDUCTANCE AND QUALITY FACTOR
CONCLUSIONS
APPENDIX A-1
LOOP GROUND-RESISTANCE DERIVATION
APPENDIX A-2
REAL PART OF COMPLEX BESSEL FUNCTION OF FIRST KIND
DERIVATIVE OF REAL PART
IMAGINARY PART OF COMPLEX BESSEL FUNCTION OF FIRST KIND
DERIVATIVE OF IMAGINARY PART
APPENDIX A-3
COMPLETE ELLIPTIC INTEGRAL OF FIRST KIND
COMPLETE ELLIPTIC INTEGRAL OF SECOND KIND
APPENDIX A-4
SERIES TO PARALLEL CIRCUIT TRANSFORMATION
APPENDIX A-5
TRANSFORMER MODEL INPUT IMPEDANCE
REFERENCES
APPENDIX B. CURRENT SHEET FORMULA FOR CALCULATION OF LOOP INDUCTANCE
SAMPLE INDUCTANCE CALCULATION
REFERENCES
APPENDIX C. LOOP INDUCTANCE AND QUALITY FACTOR TABLES
ABSTRACT
APPENDIX D. ELECTRICAL CHARACTERISTICS OF WIRE AND CABLE
CAPACITANCE OF PARALLEL CONDUCTORS
INDUCTANCE OF PARALLEL CONDUCTORS
APPENDIX E. VEHICLE DETECTION SENSITIVITY FORMULAS FOR RECTANGULAR LOOPS
ABSTRACT
INTRODUCTION
VEHICLE DETECTION SENSITIVITY THEORY
VEHICLE MODEL
REINFORCING STEEL MODEL
CIRCUIT MODEL FOR ONE-TURN LOOP
Circuit Equations for One-Turn Loop
Inductive-Loop Driving-Point Impedance
Inductive-Loop Sensitivity
CIRCUIT MODEL FOR TWO-TURN LOOP
Circuit Equations for Two-Turn Loop
CIRCUIT EQUATIONS FOR MULTITURN LOOP
VEHICLE DETECTION SENSITIVITY FOR A MULTITURN LOOP
INDUCTIVE-LOOP DETECTOR SENSITIVITY
LOOP-DETECTOR SENSITIVITY MEASURED DATA AND CALCULATED RESULTS
LOOP-DETECTOR SENSITIVITY COMPUTER PROGRAM
MEASURED-LOOP DETECTOR SENSITIVITY DATA
COMPARISON BETWEEN MEASURED AND CALCULATED SENSITIVITY DATA
EFFECT OF LOOP TURNS ON SENSITIVITY
EFFECT OF LOOP VOLUME ON SENSITIVITY
EFFECT OF LEAD-IN CABLE INDUCTANCE ON SENSITIVITY
EFFECT OF MESH ON SENSITIVITY
EFFECT OF LEAD-IN CABLE AND MESH ON SENSITIVITY
RESULTS AND CONCLUSIONS
REFERENCES
APPENDIX F. DIGITAL FREQUENCY-SHIFT ELECTRONICS UNIT ANALYSIS
ABSTRACT
ANALYSIS
APPENDIX G. DIGITAL RATIOED FREQUENCY-SHIFT ELECTRONICS UNIT ANALYSIS
ABSTRACT
ANALYSIS
APPENDIX H. DIGITAL PERIOD-SHIFT ELECTRONICS UNIT ANALYSIS
ABSTRACT
ANALYSIS
APPENDIX I. DIGITAL RATIOED PERIOD-SHIFT ELECTRONICS UNIT ANALYSIS
ABSTRACT
ANALYSIS
APPENDIX J. NEMA DETECTOR STANDARDS EXCERPTS
INTRODUCTION
NEMA TS 1 AND TS 2 TRAFFIC CONTROL SYSTEMS
DETECTOR TERMS AND DEFINITIONS
1.2.4 DETECTION
1.2.4.1 Advisory Detection
1.2.4.2 Passage Detection
1.2.4.3 Presence Detection
1.2.5 DETECTOR
1.2.5.1 Bidirectional Detector
1.2.5.2 Calling Detector
1.2.5.3 Classification Detector
1.2.5.4 Directional Detector
1.2.5.5 Extension Detector
1.2.5.6 Infrared Detector
1.2.5.7 Light-Sensitive Detector
1.2.5.8 Loop Detector
1.2.5.9 Magnetic Detector
1.2.5.10 Magnetometer Detector
1.2.5.11 Nondirectional Detector
1.2.5.12 Pedestrian Detector
1.2.5.13 Pneumatic Detector
1.2.5.14 Pressure-Sensitive Detector
1.2.5.15 Radar Detector
1.2.5.16 System Detector
1.2.5.17 Side-Fire Detector
1.2.5.18 Sound-Sensitive Vehicle Detector
1.2.5.19 Ultrasonic Detector
1.2.6 DETECTOR MODE
1.2.7 INDUCTIVE LOOP DETECTOR SYSTEM
1.2.8 INDUCTIVE LOOP DETECTOR UNIT
1.2.9 LEAD-IN CABLE
1.2.10 OUTPUT
1.2.10.1 Extension Output
1.2.10.2 Delayed Output
1.2.11 PROBE
1.2.12 SENSOR
1.2.13 VEHICLE DETECTOR SYSTEM
1.2.14 ZONE OF DETECTION (SENSING ZONE)
ENVIRONMENTAL TESTING OF DETECTORS
2.8 LOOP DETECTOR UNIT TESTS
2.8.1 Environmental Requirements
2.8.1.1 Voltage, DC Supply
2.8.1.2 Temperature and Humidity
2.8.1.3 Transients, DC Powered Units
2.8.1.4 Transients, Loop Detector Input Terminals
2.8.1.5 Vibration
2.8.1.6 Shock
MINIMUM REQUIREMENTS FOR DETECTORS
6.5 INDUCTIVE LOOP DETECTOR UNITS
6.5.1 Loop Detector Unit Definitions
6.5.1.1 Channel
6.5.1.2 Crosstalk
6.5.1.3 Detector Mode
6.5.1.4 Lead-In Cable
6.5.1.5 Loop Detector System
6.5.1.6 Loop Detector Unit
6.5.1.7 Reset Channel
6.5.1.8 Reset Unit
6.5.1.9 Sensor Loop
6.5.1.9 Vehicle Detector System
6.5.1.9 Zone of Detection
6.5.2 Functional Standards
6.5.2.1 Operation
6.5.2.2 Configurations and Dimensions
6.5.2.2.1 Configurations
6.5.2.2.2 Dimensions
6.5.2.3 Accessibility
6.5.2.4 Material and Construction of Rigid Printed Circuit Assemblies
6.5.2.4.1 Materials
6.5.2.4.2 Component Identification
6.5.2.5 Power Inputs
6.5.2.5.2 Low Supply Voltage Automatic Reset
6.5.2.6 Logic Ground
6.5.2.7 Earth Ground
6.5.2.8.1 Low or Active State
6.5.2.8.2 High or Inactive State
6.5.2.8.3 Transition Voltage Zone Of Input Circuitry
6.5.2.8.4 External Transition Time
6.5.2.8.5 Maximum Current
6.5.2.8.6 Signal Recognition
6.5.2.8.7 Activation of Delay/Extension Feature
6.5.2.8.8 Activation of Detector Unit Address Feature
6.5.2.9 Data Receive (RX) Input
6.5.2.9.1 Mark State (Binary 1)
6.5.2.9.2 Space State (Binary 0)
6.5.2.9.3 Other States
6.5.2.9.4 Transient Withstand
6.5.2.10 Loop Inputs
6.5.2.11 Loop/Lead in Electrical Properties
6.5.2.12Test Loop Configurations
6.5.2.13 Test Vehicle Definition
6.5.2.14 Sensitivity
6.5.2.15 Sensitivity Control
6.5.2.16 Approach Speed
6.5.2.17 Modes of Operation
6.5.2.17.1 Presence
6.5.2.17.2 Pulse
6.5.2.18 Recovery from Sustained Occupancy
6.5.2.19 Response Time
6.5.2.19.1 Variation in Response Time
6.5.2.20 Tuning
6.5.2.21 Self-Tracking
6.5.2.22 Recovery From Reset
6.5.2.23 Crosstalk Avoidance
6.5.2.24 Delay/Extension
6.5.2.24.1 Delay
6.5.2.24.2 Extension
6.5.2.25 Controls and Indicators
6.5.2.26 Outputs
6.5.2.26.1 Solid State Channel Detection Outputs
6.5.2.26.2 Channel Status Outputs
6.5.2.26.3 Channel Status Reporting
6.5.2.26.4 Data Transmit Output (TX)
6.5.2.26.4.1 Mark State (Binary 1)
6.5.2.26.4.2 Space State (Binary 0)
6.5.2.26.4.3 High Impedance State
6.5.2.26.4.4 Output Impedance During Power Off
6.5.2.26.4.5 TX Output Shorts
6.5.2.26.4.6 Rise/Fall Time
6.5.2.26.4.7 Transient Withstand
6.5.2.27 Communication Port Functional Requirements
6.5.2.27.1 Communication Port Electrical Requirements
6.5.2.27.2 Baud Rate
6.5.2.27.3 Communication Parameters
6.5.2.27.4 Slot Addresses
6.5.2.28 Electrical Connections
6.5.2.28.1 Connector Description
6.5.2.28.2 Connector Terminations
6.5.2.28.3 Type A Two Channel Without Delay / Extension Timing
6.5.2.28.4 Type B Four Channel Without Delay / Extension Timing
6.5.2.28.4 Type C Two Channel With Delay / Extension Timing
REFERENCES
APPENDIX K. CALTRANS TRANSPORTATION ELECTRICAL EQUIPMENT SPECIFICATIONS (TEES) FOR ELECTRONICS UNITS AND MAGNETIC DETECTORS
SECTION 1. GENERAL REQUIREMENTS
5.1.1 CHANNEL INDEPENDENCE AND POWER REQUIREMENTS
5.1.2 SENSOR UNIT FEATURES
5.1.3 OUTPUT DEVICE TYPE
5.1.4 OUTPUT SIGNAL CHARACTERISTICS
5.1.5 INTERFACE REQUIREMENTS
5.1.6 OUTPUT DEVICE SWITCHING TIME
5.1.7 SERIAL OUTPUT DEFINITION
5.1.8 ELECTRICAL SURGE PROTECTION
SECTION 2. MODEL 222E AND 224E LOOP DETECTOR SENSOR UNIT REQUIREMENTS
5.2.1 OUTPUT SIGNAL DEFINITION
5.2.2 MALFUNCTIONING LOOP SIGNAL DEFINITION
5.2.3 SUPPORTED LOOP CONFIGURATIONS
5.2.4 INDUCTANCE AND Q RANGE OF SUPPORTED LOOP AND LEAD-IN CABLE ASSEMBLIES
5.2.5 TRANSFORMER ISOLATION OF LOOP INPUTS
5.2.6 NUMBER OF SUPPORTED OPERATING FREQUENCIES
5.2.7 DRIFT COMPENSATION OF TUNING CIRCUITS
5.2.8 PULSE AND PRESENCE MODE SUPPORT
5.2.8.1: Pulse Mode Description
5.2.8.2: Presence Mode Description
5.2.9 SENSITIVITY
5.2.10 RESPONSE TIME
5.2.11 NORMAL OPERATION TIME
5.2.12 TRACKING RATE
5.2.13 TRACKING RANGE
5.2.14 TEMPERATURE CHANGE
SECTION 3. MAGNETIC DETECTOR REQUIREMENTS
5.3.1 MODEL 231E MAGNETIC DETECTOR SENSING ELEMENT
5.3.1.1 Design Requirements
5.3.1.2 DC Resistance
5.3.2 MODEL 232E TWO CHANNEL MAGNETIC DETECTOR SENSING UNIT
5.3.2.1 Output Signal Definition
REFERENCES
APPENDIX L. CLASSIFICATION OF SENSOR SYSTEMS BY SENSOR DENSITY LEVEL
ABSTRACT
TERMINOLOGY
UNCOORDINATED SIGNALS or UNCOORDINATED CONTROL
TIME-BASED COORDINATION or TIME-BASED COORDINATED CONTROL
INTERCONNECTED CONTROL
TRAFFIC ADJUSTED CONTROL
TRAFFIC RESPONSIVE CONTROL
TRAFFIC ADAPTIVE CONTROL
SENSOR WEB DENSITY LEVELS
SENSOR WEB DENSITY LEVEL 0.0
SENSOR WEB DENSITY LEVEL 0.5
SENSOR WEB DENSITY LEVEL 1.0
SENSOR WEB DENSITY LEVEL 1.5
SENSOR WEB DENSITY LEVEL 2.0
SENSOR WEB DENSITY LEVEL 2.5
SENSOR WEB DENSITY LEVEL 3.0
SENSOR WEB DENSITY LEVEL 3.5
SENSOR WEB DENSITY LEVEL 4.0
GENERAL OBSERVATIONS
REFERENCES
APPENDIX M. EXTENT AND CAUSES OF INDUCTIVE-LOOP FAILURES
STUDIES SUMMARIZED IN THIS APPENDIX
OREGON STUDY
OREGON SURVEY RESULTS
OREGON CONCLUSIONS AND RECOMMENDATIONS
WASHINGTON STUDY
WASHINGTON SURVEY RESULTS
WASHINGTON CONCLUSIONS AND RECOMMENDATIONS
MINNESOTA STUDY
MINNESOTA SURVEY RESULTS
MINNESOTA CONCLUSIONS AND RECOMMENDATIONS
NEW YORK STUDY
NEW YORK SURVEY RESULTS
NEW YORK CONCLUSIONS AND RECOMMENDATIONS
APPENDIX N. GROUNDING (DESIGN GUIDELINES)
SECTION I—REASONS FOR GROUNDING
1. SAFETY GROUNDING
2. SYSTEM GROUNDING
3. LIGHTNING DISCHARGE
SECTION II—CALCULATION OF RESISTANCE TO GROUND
1. GENERAL
2. SOIL RESISTIVITY
3. GROUND ELECTRODE RESISTANCE TO GROUND
3.1 Ground Rods
3.2 Pedestals
3.3 Plate Electrodes
3.4 Wire Grids
3.5 Multiple Rods
3.6 Combination Rod and Wire Grids
3.7 Single Wire
3.8 Summary of Calculations
3.9 Application
3.10 Problem Areas
3.11 Application Guidelines
SECTION III—EFFECTS OF LIGHTNING
1. GENERAL
2. DESIGN CRITERIA
3. POWER SURGES
4. OTHER SOURCES OF POSSIBLE DAMAGE
SECTION IV—SUMMARY OF DESIGN GUIDELINES
1. TRAFFIC SIGNAL SYSTEMS
SECTION V—REFERENCES
APPENDIX O. GROUNDING (MAINTENANCE GUIDELINES)
SECTION I—TRAFFIC SIGNAL GROUNDING
1. HYDRO GROUNDS
2. SERVICE GROUNDS
3. CABINET GROUNDS
4. SPECIAL SOIL CONDITIONS
5. SYSTEM GROUND
6. ROUTINE INSPECTION
7. EMERGENCY INSPECTION
8. MEASUREMENTS
9. STEEL FOOTINGS
10. GROUND RODS
11. GOOD PRACTICE
SECTION II—REFERENCES
APPENDIX Q. REGISTERED TRADEMARKS
CHAPTER 1. INTRODUCTION
CHAPTER 2. SENSOR TECHNOLOGY
CHAPTER 3. SENSOR APPLICATIONS
CHAPTER 4. IN-ROADWAY SENSOR DESIGN
CHAPTER 5. SENSOR INSTALLATION TECHNIQUES
CHAPTER 6. SENSOR MAINTENANCE
APPENDIX A. INDUCTIVE-LOOP SYSTEM EQUIVALENT CIRCUIT MODEL
APPENDIX D. ELECTRICAL CHARACTERISTICS OF WIRE AND CABLE
APPENDIX E. VEHICLE DETECTION SENSITIVITY FORMULAS FOR RECTANGULAR LOOPS
APPENDIX F. DIGITAL FREQUENCY-SHIFT ELECTRONICS UNIT ANALYSIS
APPENDIX G. DIGITAL RATIOED FREQUENCY-SHIFT ELECTRONICS UNIT ANALYSIS
APPENDIX H. DIGITAL PERIOD SHIFT ELECTRONICS UNIT ANALYSIS
APPENDIX I. DIGITAL RATIOED PERIOD-SHIFT ELECTRONICS UNIT ANALYSIS
APPENDIX L. CLASSIFICATION OF SENSOR SYSTEMS BY SENSOR DENSITY LEVEL
APPENDIX M. EXTENT AND CAUSES OF INDUCTIVE-LOOP FAILURES
APPENDIX N. GROUNDING (DESIGN GUIDELINES)
APPENDIX O. GROUNDING (MAINTENANCE GUIDELINES)
CHAPTER 1. INTRODUCTION
CHAPTER 2. SENSOR TECHNOLOGY
CHAPTER 3. SENSOR APPLICATIONS
CHAPTER 4. IN-ROADWAY SENSOR DESIGN
CHAPTER 5. SENSOR-INSTALLATION TECHNIQUES
CHAPTER 6. SENSOR MAINTENANCE
APPENDIX A. INDUCTIVE-LOOP SYSTEM EQUIVALENT CIRCUIT MODEL
APPENDIX B. CURRENT SHEET FORMULA FOR CALCULATION OF LOOP INDUCTANCE
APPENDIX C. LOOP INDUCTANCE AND QUALITY FACTOR TABLES
APPENDIX D. ELECTRICAL CHARACTERISTICS OF WIRE AND CABLE
APPENDIX E. VEHICLE DETECTION SENSITIVITY FORMULAS FOR RECTANGULAR LOOPS
APPENDIX J. NEMA DETECTOR STANDARDS EXCERPTS
APPENDIX K. CALTRANS TRANSPORTATION ELECTRICAL EQUIPMENT SPECIFICATIONS (TEES) FOR ELECTRONICS UNITS AND MAGNETIC DETECTORS
APPENDIX M. EXTENT AND CAUSES OF INDUCTIVE LOOP FAILURES
APPENDIX N. GROUNDING (DESIGN GUIDELINES)
APPENDIX O. GROUNDING (MAINTENANCE GUIDELINES)
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